Liquid enclosing type vibration isolating apparatus

Abstract

To provide a liquid enclosing type vibration isolating apparatus capable of achieving two resonance characteristics by one orifice path, in a liquid enclosing type vibration isolating apparatus including a main liquid chamber a portion of a chamber wall of which is constituted by a vibration isolating base member, an auxiliary liquid chamber a portion of a chamber wall of which is constituted by a first diaphragm 18 , and an orifice path for communicating the main liquid chamber and the auxiliary liquid chamber, an orifice member forming the orifice path is provided with a partition wall for partitioning the orifice path and the auxiliary liquid chamber, and a portion of the partition wall is constituted by a second diaphragm constituted by a flexible rubber-like elastic film facing the auxiliary liquid chamber.

1. A liquid enclosing type vibration isolating apparatus comprising:
 a first attaching piece to be attached to one of a vibration source side and a support side; 
 a second attaching piece to be attached to other of the vibration source side and the support side; 
 a vibration isolating base member comprising an elastic member interposed between the first attaching piece and the second attaching piece; 
 a first diaphragm comprising an elastic member; 
 a main liquid chamber a portion of a chamber wall of which is constituted by the vibration isolating base member and which is filled with a liquid; 
 an auxiliary liquid chamber a portion of a chamber wall of which is constituted by the first diaphragm and which is filled with the liquid; and 
 an orifice member forming an orifice path of communicating the main liquid chamber and the auxiliary liquid chamber by a main liquid chamber side opening opened to the main liquid chamber and an auxiliary liquid chamber side opening opened to the auxiliary liquid chamber; 
 wherein the orifice member includes a partition wall for partitioning the orifice path and the main liquid chamber or the auxiliary liquid chamber, and the partition wall at a portion of the orifice path between the main liquid chamber side opening and the auxiliary liquid chamber side opening is constituted by a second diaphragm comprising a flexible elastic film facing the main liquid chamber or the auxiliary liquid chamber, 
 wherein the second diaphragm partitions the orifice path and the main liquid chamber or the auxiliary liquid chamber; 
 wherein the partition wall at a portion of the orifice path is provided with an opening portion opened to the main liquid chamber or the auxiliary liquid chamber, and 
 wherein the second diaphragm is formed by fixing the flexible elastic film over the whole periphery of the opening portion so as to close the opening portion. 
 
     
     
       2. The liquid enclosing type vibration isolating apparatus according to  claim 1 , wherein the second attaching piece is constituted by a cylindrical shape, the first diaphragm is attached to the second attaching piece to form a liquid chamber filled with a liquid between the first diaphragm and the vibration isolating base member, the liquid chamber is partitioned to the main liquid chamber and the auxiliary liquid chamber by the dividing unit, and the dividing unit comprises the orifice member in a ring shape fitted to an inner side of a peripheral wall portion of the second attaching piece and forming the orifice path, and a dividing wall partitioning the main liquid chamber and the auxiliary liquid chamber in an axis direction on an inner side of the orifice member. 
     
     
       3. The liquid enclosing type vibration isolating apparatus according to  claim 2 , wherein the partition wall at a portion of the orifice path is provided with an opening portion opened to the main liquid chamber or the auxiliary liquid chamber, and the opening portion is closed by vulcanizing to mold a rubber film to thereby form the second diaphragm. 
     
     
       4. The liquid enclosing type vibration isolating apparatus according to  claim 2 , wherein the second diaphragm is provided by a length in a peripheral direction of a half or more of a length in the peripheral direction of the orifice path in the orifice path formed along the peripheral direction of the orifice member.